• Journal of Ship and Ocean Technology
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• v.10 no.4
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• pp.34-48
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• 2006

The visual observation of wave condition depends on the observer's skill and experience. Also, the environmental conditions such as light and cloud heavily influence the visual measurement. In the speed test of sea trial, the wave measurement should be objective and accurate. In this paper, the problems of visual measurement and their effects on speed test are described. To overcome those problems, we developed the wave measurement system using commercial marine X-band radar, WaveFinder. The system installed at inland base was calibrated by waverider buoy and then the system's operability was defined. Onboard tests had also been performed three times for formal wave measurement to correct the ship speed. The results illustrated very good agreement with visual observation by experts. It can be concluded that the system would be useful to measure wave and swell information for the sea trial, irrespective of day and night.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.44-51
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• 2008

Purpose: We performed this study to evaluate reliability on interpretation of three phase bone scintigraphy (TPBS) in patients with post-traumatic complex regional pain syndrome (PT-CRPS). Methods: Based on International Association for the Study of Pain guideline in 1994, 34 patients with PT-CRPS were selected for this study. Two nuclear medicine physicians evaluated identical TPBS according to the uptake pattern, extent and intensity of the lesion, and their agreements (kappa values) were analysed. The final diagnosis based on arbitrary criteria of each physician were compared with those obtained by the criteria for PT-CRPS established in this study, which are hyperactivity on all phases (criteria 1), hyperactivity of whole joints on delayed phase (criteria 2), and hyperactivity of either whole or FDGal joints on delayed phase (criteria 3). Results: Intra-observer agreements were good for uptake pattern, intensity, and extent on TPBS. Inter-observer agreements were also good, except extent on blood pool phase (0.55). The inter-observer agreements on final diagnosis improved when criteria 1-3 were applied (0.77-0.88), compared to when physician's own criteria were used (0.63). Those also improved from 0.29 to 0.47-0.82 for acute stage, and from 0.37 to 1.0 for chronic stage. The sensitivities of chronic stage were relatively lower to those of acute stage. Conclusions: Inter-observer's variations in diagnosis of the patients with PT-CRPS using TPBS were observed. These results were attributed to different criteria set by observers. In order to improve agreement on interpretation of TPBS, common positive criteria should be established, especially considering uptake pattern and clinical stages.

• Korean Journal of Radiology
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• v.20 no.4
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• pp.671-682
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• 2019

Objective: To investigate whether computed tomography (CT) and fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) may be applied to distinguish thymic epithelial tumors (TETs) from benign cysts in the anterior mediastinum. Materials and Methods: We included 262 consecutive patients with pathologically proven TETs and benign cysts 5 cm or smaller who underwent preoperative CT scans. In addition to conventional morphological and ancillary CT findings, the relationship between the lesion and the adjacent mediastinal pleura was evaluated qualitatively and quantitatively. Mean lesion attenuation was measured on CT images. The maximum standardized uptake value (SUVmax) was obtained with FDG-PET scans in 40 patients. CT predictors for TETs were identified with multivariate logistic regression analysis. For validation, we assessed the diagnostic accuracy and inter-observer agreement between four radiologists in a size-matched set of 24 cysts and 24 TETs using a receiver operating characteristic curve before and after being informed of the study findings. Results: The multivariate analysis showed that post-contrast attenuation of 60 Hounsfield unit or higher (odds ratio [OR], 12.734; 95% confidence interval [CI], 2.506-64.705; p = 0.002) and the presence of protrusion from the mediastinal pleura (OR, 9.855; 95% CI, 1.749-55.535; p = 0.009) were the strongest CT predictors for TETs. SUVmax was significantly higher in TETs than in cysts (5.3 ± 2.4 vs. 1.1 ± 0.3; p < 0.001). After being informed of the study findings, the readers' area under the curve improved from 0.872-0.955 to 0.949-0.999 (p = 0.066-0.149). Inter-observer kappa values for protrusion were 0.630-0.941. Conclusion: Post-contrast CT attenuation, protrusion from the mediastinal pleura, and SUVmax were useful imaging features for distinguishing TETs from cysts in the anterior mediastinum.

• Korean Journal of Radiology
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• v.23 no.3
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• pp.298-307
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• 2022

Objective: This study aimed to evaluate the effect of implementing the consensus statement from the Asian Society of Cardiovascular Imaging-Practical Tutorial 2020 (ASCI-PT 2020) on the reliability of cardiac MR with late gadolinium enhancement (CMR-LGE) myocardial viability scoring between observers in the context of ischemic cardiomyopathy. Materials and Methods: A total of 17 cardiovascular imaging experts from five different countries evaluated CMR obtained in 26 patients (male:female, 23:3; median age [interquartile range], 55.5 years [50-61.8]) with ischemic cardiomyopathy. For LGE scoring, based on the 17 segments, the extent of LGE in each segment was graded using a five-point scoring system ranging from 0 to 4 before and after exposure according to the consensus statement. All scoring was performed via web-based review. Scores for slices, vascular territories, and total scores were obtained as the sum of the relevant segmental scores. Interobserver reliability for segment scores was assessed using Fleiss' kappa, while the intraclass correlation coefficient (ICC) was used for slice score, vascular territory score, and total score. Inter-observer agreement was assessed using the limits of agreement from the mean (LoA). Results: Interobserver reliability (Fleiss' kappa) in each segment ranged 0.242-0.662 before the consensus and increased to 0.301-0.774 after the consensus. The interobserver reliability (ICC) for each slice, each vascular territory, and total score increased after the consensus (slice, 0.728-0.805 and 0.849-0.884; vascular territory, 0.756-0.902 and 0.852-0.941; total score, 0.847 and 0.913, before and after implementing the consensus statement, respectively. Interobserver agreement in scoring also improved with the implementation of the consensus for all slices, vascular territories, and total score. The LoA for the total score narrowed from ± 10.36 points to ± 7.12 points. Conclusion: The interobserver reliability and agreement for CMR-LGE scoring for ischemic cardiomyopathy improved when following guidance from the ASCI-PT 2020 consensus statement.

• Archives of Plastic Surgery
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• v.46 no.6
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• pp.535-543
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• 2019

Background A high incidence of breast animation deformity (BAD) has been reported following immediate breast reconstruction with subpectorally placed implants. The aim of this study was to assess and compare the incidence of BAD in women who underwent either subpectoral or prepectoral immediate breast reconstruction. Therefore, we developed a grading tool and tested its reproducibility in a clinical setting. Methods Video recordings of 37 women who had undergone unilateral or bilateral immediate breast reconstruction were evaluated by two consultant plastic surgeons. The degree of BAD was assessed by our grading tool, named the Nipple, Surrounding Skin, Entire Breast (NSE) grading scale, which evaluates the degree of tissue distortion in three areas of the breast. Blinded assessments were performed twice by each observer. Results Eighteen patients were reconstructed with subpectoral implant placement and 19 with prepectoral implant placement. Using the NSE grading scale, we found a significant difference in the degree of BAD between the groups, in favor of patients who underwent prepectoral immediate breast reconstruction (0.2 vs. 4, P=0.000). Inter- and intraobserver agreement was moderate (74%) to strong (88%). Conclusions The incidence and severity of BAD was significantly lower in women reconstructed with a prepectorally placed implant than in those who underwent subpectoral immediate breast reconstruction. All patients reconstructed using the subpectoral technique had some degree of BAD. The inter- and intraobserver agreements were high when using the NSE grading scale, suggesting it is an easy-to-use, reproducible scale for assessing BAD in women who undergo immediate breast reconstruction.

• Imaging Science in Dentistry
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• v.45 no.2
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• pp.81-87
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• 2015

Purpose: Contrast, sharpness, enhancement, and density can be changed in digital systems. The important question is to what extent the changes in these variables affect the accuracy of caries detection. Materials and Methods: Forty eight extracted human posterior teeth with healthy or proximal caries surfaces were imaged using a photostimulable phosphor (PSP) sensor. All original images were processed using a six-step method: (1) applying "Sharpening 2" and "Noise Reduction" processing options to the original images; (2) applying the "Magnification 1:3" option to the image obtained in the first step; (3) enhancing the original images by using the "Diagonal/"option; (4) reviewing the changes brought about by the third step of image processing and then, applying "Magnification 1:3"; (5) applying "Sharpening UM" to the original images; and (6) analyzing the changes brought about by the fifth step of image processing, and finally, applying "Magnification 1:3." Three observers evaluated the images. The tooth sections were evaluated histologically as the gold standard. The diagnostic accuracy of the observers was compared using a chi-squared test. Results: The accuracy levels irrespective of the image processing method ranged from weak (18.8%) to intermediate (54.2%), but the highest accuracy was achieved at the sixth image processing step. The overall diagnostic accuracy level showed a statistically significant difference (p=0.0001). Conclusion: This study shows that the application of "Sharpening UM" along with the "Magnification 1:3" processing option improved the diagnostic accuracy and the observer agreement more effectively than the other processing procedures.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.123-136
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• 2012

The validity of the results from observational methods such as RULA, REBA, OWAS has been one of major concerns due to their subjective characteristics in determining the posture of interests. There have been many studies regarding validity of the results from each checklist. However, most studies provided only fragmentary rather than comprehensive results in nature. This study specifically tried to analyze consistency of novice user based on intra-observer consistency and sensitivity of industrial types during MSDs(Musculoskekltal Disorders) evaluation with major checklists. In this study, twenty two novice subjects were participated to conduct MSDs evaluation for the forty five jobs from three types of industries(automobile, electronics, hospital). The main results for this study were summarized as follows; 1) The action level based on RULA was always higher than that from REBA and OWAS for all three types of industries., 2) The order of consistency from novice users was OWAS(72.7%(kappa=0.57)) RULA(54.3%(kappa=0.41)), REBA(41.0%(kappa=0.34))., 3) The percentage of agreement between 2nd and 3rd trials was higher than those between 1st and 2nd trials and between 1st and 3rd trials irrespective of industrial types during using RULA and REBA., 4) The average score of automobile industry was higher than those of hospital and electronics industries., 5) The types of jobs associated with five body parts(A1(Front), A2(Interior), A3(Rear), A4(Lower), A5(Door)) in automobile industry showed statistically significant differences in terms of MSDs scores for the body parts considered in each checklists.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.4.1-4.7
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• 2017

Background: This study is a quantitative evaluation of the influence of the mentolabial angle on perceived attractiveness and threshold values of desire for surgery. Methods: The mentolabial angle of an idealized silhouette male Caucasian profile image was altered incrementally between $84^{\circ}$ and $162^{\circ}$. Images were rated on a Likert scale by pretreatment orthognathic patients (n = 75), lay people (n = 75) and clinicians (n = 35). Results: A mentolabial angle of approximately $107^{\circ}$ to $118^{\circ}$ was deemed the most attractive, with a range of up to $140^{\circ}$ deemed acceptable. Angles above or below this range were perceived as unattractive, and anything outside the range of below $98^{\circ}$ or above $162^{\circ}$ was deemed very unattractive. A deep mentolabial angle ($84^{\circ}$) or an almost flat angle ($162^{\circ}$) was deemed the least attractive. In terms of threshold values of desire for surgery, for all groups, a threshold value of ${\geq}162^{\circ}$ and ${\leq}84^{\circ}$ indicated a preference for surgery, although clinicians were least likely to suggest surgery. The clinician group was the most consistent, and for many of the images, there was some variation in agreement between clinicians and lay people as to whether surgery is required. There was even more variability in the assessments for the patient group. Conclusions: It is recommended that in orthognathic and genioplasty planning, the range of normal variability of the mentolabial angle, in terms of observer acceptance, is taken into account as well as threshold values of desire for surgery. The importance of using patients as observers in attractiveness research is stressed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.6
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• pp.309-315
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• 2019

Objectives: The aim of this study was to evaluate the validity of the existing classification and difficulty index of impacted mandibular third molars in clinical situations and propose a more practical classification system. Materials and Methods: This study included 204 impacted mandibular third molars in 154 patients; panoramic x-ray images were obtained before tooth extraction. Factors including age, sex, and pattern of impaction were investigated. All impacted third molars were classified and scored for spatial relationship (1-5 points), depth (1-4 points), and ramus relationship (1-3 points). All variables were measured twice by the same observer at a minimum interval of one month. Finally, the difficulty index was defined based on the total points scored as slightly difficult (3-4 points), moderately difficult (5-7 points), very difficult (8-10 points), and extremely difficult (11-12 points). Results: The strength of agreement of the total points scored and difficulty index were 0.855 and 0.746, respectively. Most cases were classified as moderately difficult (73.0%). Although only 13 out of 204 cases (6.4%) were classified as extremely difficult, patients classified as extremely difficult were the oldest (P<0.05). Conclusion: For difficulty classification, the authors propose one more difficult category beyond the existing three-step difficulty index: the clinician should consider the patient's age in the difficulty index evaluation.

• Journal of Yeungnam Medical Science
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• v.36 no.3
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• pp.231-240
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• 2019

Background: We sought to determine the value of combining diffusion-weighted (DW) and perfusion-weighted (PW) sequences with a conventional magnetic resonance (MR) sequence to assess solid components of borderline ovarian tumors (BOTs) and stage I carcinomas. Methods: Conventional, DW, and PW sequences in the tumor imaging studies of 70 patients (BOTs, n=38; stage I carcinomas, n=32) who underwent surgery with pathologic correlation were assessed. Two independent radiologists calculated the parameters apparent diffusion coefficient (ADC), $K^{trans}$ (vessel permeability), and $V_e$ (cell density) for the solid components. The distribution on conventional MR sequence and mean, standard deviation, and 95% confidence interval of each DW and PW parameter were calculated. The inter-observer agreement among the two radiologists was assessed. Area under the receiver operating characteristic curve (AUC) and multivariate logistic regression were performed to compare the effectiveness of DW and PW sequences for average values and to characterize the diagnostic performance of combined DW and PW sequences. Results: There were excellent agreements for DW and PW parameters between radiologists. The distributions of ADC, $K^{trans}$, and $V_e$ values were significantly different between BOTs and stage I carcinomas, yielding AUCs of 0.58 and 0.68, 0.78 and 0.82, and 0.70 and 0.72, respectively, with ADC yielding the lowest diagnostic performance. The AUCs of the DW, PW, and combined PW and DW sequences were $0.71{\pm}0.05$, $0.80{\pm}0.05$, and $0.85{\pm}0.05$, respectively. Conclusion: Combining PW and DW sequences to a conventional sequence potentially improves the diagnostic accuracy in the differentiation of BOTs and stage I carcinomas.